Search PubMed⌕ Search

Biomedical subjects

A D Ho

Publications and source records attributed to A D Ho.

248 records · Page 14Linked to original sources

Capping of lymphocytes for carrier detection in Duchenne muscular dystrophy: technical problems and a review of the literature.

There has been considerable interest in capping of lymphocytes in patients with Duchenne muscular dystrophy (DMD). However, the results from different authors are controversial. We have investigated cap formation in thirteen families with DMD, using a method standardized in our laboratory, and could establish diminished capping in all 12 patients and in 12 of the 13 mothers. By examining cap formation simultaneously with whole polyvalent antiserum, with F(ab)2 fragment of polyvalent antiserum, and with monospecific antisera we could also confirm this observation of defective capping in 7 patients and 4 carriers, as compared to 9 control subjects likewise examined. We have indications that treatment of the lymphocytes under unfavourable conditions e.g. preincubation in buffer solution might accentuate the decrease of lymphocyte capping in patients and carriers.

Adolescent↗

Progressive multifocal leukoencephalopathy in a patient with Hodgkin's disease.

This is a report on a 78-year-old patient with Hodgkin's disease of mixed cell type in stage III B, who, because of his age, underwent only mild cytostatic therapy. Two months after beginning of treatment, cerebellar neurological symptoms developed. He died of bronchopneumonia 3 months later. At autopsy progressive multifocal leukoencephalopathy with multiple demyelinated areas in the cerebellum was established. Paracristallinic structures within nuclei of glial cells resembling papovavirus formations were detected by electron microscopy.

Aged↗

Leukocyte alkaline phosphatase in malignancies.

The leukocyte alklaine phosphatase (LAP) levels were determined in 183 patients with malignant diseases and 71 normal controls. The median LAP scores were 64 units (range 0 to 290) for the patients and 55 (range 2 to 158) for the controls, respectively, and no significant difference could be established. When analyzed according to primary malignancy, only in patients with Hodgkin's disease (n = 14) was the median value higher than normal (p less than 0.001). In patients with distant metastases (n = 48), higher LAP levels were demonstrated (M = 76, range 21 to 290) as compared to patients with no evidence of metastases (M = 53, range 0 to 229), (p less than 0.01). Thus, LAP activity has very limited value in the diagnosis of malignancies. Its elevation in the presence of malignant disease might, however, indicate metastases.

Adult↗

Purine degradative enzymes in circulating malignant cells of patients with chronic B cell neoplasia.

Previous reports have shown that the purine degradative enzymes adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP) and ecto-5'-nucleotidase (5'NT), play an important role in the normal development of lymphocytes and that investigations of these enzymes are of value in defining subsets of lymphoid malignancies of T-cell origin. Pharmacological inhibition of one of these enzymes has been found to be an effective treatment for a few lymphatic neoplasia. We have studied the activities of the above enzymes in the circulating malignant cells of 25 patients with B-chronic lymphatic leukemia (B-CLL), four patients with B prolymphocytic leukemia (PLL), seven patients with leukemic centrocytic lymphoma (CC), 18 patients with hairy cell leukemia (HCL) and 16 patients with immunocytoma (IC). For comparison, the blasts of nine patients with 'common' acute lymphatic leukemia (cALL) and normal T (n = 12) and B (n = 8) cells were simultaneously investigated. Despite morphologic similarity, the leukemic cells of the chronic B cell malignancies demonstrate different enzyme patterns. B-CLL is characterized by very low activities of all the enzymes ADA, PNP and 5'NT. In the cells of HCL the highest values of PNP are found. The leukemic cells of IC are characterized by low levels of ADA but moderate levels of PNP and high levels of 5'NT. Thus some of the entities of B malignancies show typical enzyme patterns which might be of importance in defining maturation stages of the disease. The differences in these enzyme patterns can also be made use of in therapy with enzyme inhibitors such as deoxycoformycin.

5'-Nucleotidase↗

Polymorphism of the human Ha-ras oncogene locus in chronic lymphocytic and chronic myelogenous leukemia.

DNA from white blood cells from healthy controls demonstrates a restriction fragment length polymorphism (RFLP) of the Ha-ras oncogene locus after cleavage with the restriction enzymes BamH I or MspI plus HpaII, representing frequent and rare alleles. We have studied the RFLP of 15 patients with B-cell chronic lymphocytic (CLL) and of 16 patients with chronic myelogenous leukemia (CML). As in healthy controls the RFLP in the leukemic cells indicates the occurrence of frequent and rare Ha-ras alleles. But rare alleles are not more frequent in the patients than in the healthy control group. The frequency of rare Ha-ras alleles also does not differ between chronic lymphocytic and chronic myelogenous leukemia. While rare alleles of this oncogene locus occur in CML and CLL as frequently as in healthy controls, they do not reflect an inherent increased risk for chronic leukemia in man.

Alleles↗

Systemic bone marrow disorders: characterization with proton chemical shift imaging.

In a prospective clinical study, 26 patients (22 with malignant lymphoma and 4 with myelofibrosis) and 9 healthy volunteers were examined by conventional magnetic resonance and proton chemical shift imaging (CSI; modified Dixon method). On the basis of the CSI data, a quantitative evaluation of the relative fat and water signal fractions in regions of interest of the femur, pelvis, and spine was performed. In 16 of 17 patients with biopsy-proven bone marrow disorders, CSI revealed a significant reduction in the fat fraction of the bone marrow relative to that of normal volunteers. The visual assessment could detect only 14 of the 17 pathological cases.

Bone Marrow↗

Proton chemical shift imaging of bone marrow for monitoring therapy in leukemia.

In three patients with different forms of leukemia, follow-up examinations before, during, and after chemotherapy and bone marrow transplantation were performed by proton chemical shift imaging (1H-CSI). The relative fat and water fractions were computed in representative regions of the marrow in the femur, pelvis, and lumbar spine. On serial examinations the fat fractions increased over time, in agreement with the responses to therapy proven by bone marrow biopsies from the iliac crest. These preliminary results suggest a role for magnetic resonance and CSI in the monitoring of therapy in leukemia and systemic neoplastic diseases.

Acute Disease↗

Ceftriaxone for the treatment of febrile episodes in nonneutropenic patients with hematooncological disease or HIV infection: comparison of outpatient and inpatient care.

BACKGROUND: Patients with hematooncological disease or HIV infection and febrile episodes are usually treated in hospital with broad-spectrum antibiotics. The aim of this observational study was to assess the feasibility of ambulatory parenteral antibiotic therapy in hematooncological or HIV-infected patients with confirmed or suspected infection. METHODS: The results in an outpatient treatment group were compared with those obtained in a group initially treated in hospital. Data were gathered on 90 outpatients and 72 inpatients. The inclusion criteria were fever > or =37.5 degrees C with an identified focus of infection, fever > or =38.0 degrees C of suspected bacterial origin with no identified focus of infection, leukocytosis > or =9,000/microl or C-reactive protein elevation > or =10 mg/l. RESULTS: Eighty outpatients and 69 inpatients were evaluable. Treatment in the outpatient group was begun with ceftriaxone. This led to defervescence in 87.5% of cases. The mean treatment duration was 7.1 days. Comparison of results in the outpatients with those initially hospitalized for treatment showed similar success rates. The mean hospital stay in the latter group was 12.9 days. CONCLUSIONS: Ceftriaxone represents an effective treatment for outpatient management of febrile episodes in patients with hematooncological disease or HIV infection. Outpatient treatment is more cost-effective than inpatient care.

Adolescent↗

Induction of molecular remission by donor peripheral blood leukocyte therapy in patients relapsing with extramedullary blastic phase chronic myeloid leukemia after allogeneic bone marrow transplantation.

Two patients with chronic myeloid leukemia (CML) who relapsed in blastic transformation after allogeneic bone marrow transplantation (BMT) were treated with infusions of leukapheresed peripheral blood mononuclear cells from their original donor. At relapse, their disease was characterized by symptomatic extramedullary deposits of leukemia with minimal (PCR positive, cytologically negative) involvement of bone marrow. Treatment with donor cell infusions was associated with clinical remission, return of full donor chimerism and loss of the BCR-ABL transcript detectable in bone marrow before donor leukocyte infusion (molecular remission). Donor leukocyte infusions should be considered for therapy of relapsed blastic phase CML after allogeneic BMT, especially when the relapse is primarily extramedullary and responsive to local and systemic cytoreductive therapy. However, severe GVHD and CNS relapse remain obstacles to achieving a successful long-term outcome.

Adult↗